Method and apparatus for singulating, debarking, scanning and automatically sawing and sorting logs into lengths

ABSTRACT

A log handling and cutting system which cuts logs into lengths, and allows for maximum use of fiber. The system includes equipment for singulating the logs, optimally removing the bark from the logs, scanning the true log image, cutting the logs to length, and sorting the cut logs arranged in a sequence of coupled operations. The logs are singulated using a dual quadrant singulation system to provide maximum singulation reliability, thereby allowing a single operator to attend to this process. Once singulated, the logs are fed automatically into a debarker where the diameter and volume are scanned and debarker-operating parameters are set for optimum bark removal. The log is then scanned, tree length, using a unique scanning system, which determines the true image of the log. This enables the determination by computer of the optimum bucking solution of the log as well as a proper sorting of the optimum random lengths. The saws are adjusted in response to the computer solution and the log is positioned by a positioner according to a computer generated reference datum. This results in the log being positioned for cutting to the optimum random lengths. A command signal is sent from the computer to the log sorting system, which tracks the position of the random lengths and allows them to be sorted to the appropriate sort storage bin.

FIELD OF THE INVENTION

This invention relates to a method and apparatus for singulating,debarking, scanning and automatically sawing and sorting logs intolengths. More particularly, this invention relates to a high productsystem and apparatus for processing raw logs into debarked optimumlengths for sawing into the maximum amount of lumber per log.

BACKGROUND OF THE INVENTION

For raw logs to be cost effectively processed into random lengthswithout bark for use in a sawmill, it is important that this process isdone with speed, accurate information obtained about the log, andaccurate cutting into the maximum number of usable lumber per log. Thespeed requirement is determined in part by the efficient singulation ofthe logs from a log pile into the log processing system, in part by therate at which bark can be removed optimally, with a minimum amount ofwhite waste, in part by the rate at which the log can be quickly andaccurately positioned and cut by the saws and in part by the rapideffective removal system of the random lengths. The accuracy of theinformation obtained about a log is determined by the type of conveyingsystem, the type of scanner and whether the log is scanned with bark onor bark off. The accuracy of cutting the logs into lengths is determinedin part by the required log process speed and in part by the system andequipment in which the log is positioned relative to the saw.

Considerable effort has been expended over the years to developefficient and high speed log processing systems. The prior art that hasbeen developed includes equipment and systems disclosed in the U.S.patents listed below.

U.S. Pat. No. 5,119,930, granted Jun. 9, 1992, Stelter, discloses andprotects a single quadrant-type log sorter. Stelter, in FIGS. 1 and 2,illustrates in dotted lines, a counterweight 70 which reduces the forcenecessary to raise the quadrant 16. Stelter also discusses at column 4,lines 53-56, the use of a double-acting cylinder 56 so pressure may beprovided on both sides of a piston to raise and lower the quadrant andrectify a portion of the live load. Stelter does not, however, disclosedual quadrants.

U.S. Pat. No. 5,722,475, granted Mar. 3, 1998, Lammi, discloses a designof ring type debarker using rotary cutting heads 23. The ring or rotor 4can be varied in speed, as stated in the abstract, and in column 2,lines 60-63. The speed of the rotor disk 4 can be adjusted continuouslydue to variations in log diameter, surface finish, irregularities andthe like. It is mentioned in column 2, lines 64-67, that the rotationalspeed of the cutting head should be kept nearly constant regardless ofvariations in the rotor speed. Lammi therefore does not disclosevariable ring or rotor speed or variable force on the cutting blades.

U.S. Pat. No. 4,609,020, granted Sep. 2, 1986, Hutson, is one of severalHutson patents which disclose a log debarker system which has a rotorassembly 26 which uses a plurality of debarking tools 28 (knives), thecombination rotating in a rotor housing assembly 24. There is no mentionof varying the force on the debarking tools 28 or rotor or log feedspeed as a function of diameter.

U.S. Pat. No. 5,117,881, granted Jun. 2, 1992, Simpson, assigned toNicholson Manufacturing Company, discloses a ring type debarkingapparatus which includes counterbalance weights 64 for rotary cutters22. The counterbalance weights 64 offset centrifugal and gravitationalforces. The debarker also includes rotary cutting units 18 on ends ofswing arms 24. The debarker ring 22 rotates (see column 2, lines 8-9)but presumably at a constant speed. There is no mention of varying ringspeed, tool tip force or log feed speed as a function of log diameter.

U.S. Pat. No. 4,330,019, granted May 18, 1982, Murphy et al., disclosesa sawmill for cutting logs into lengths which allows for maximum use ofthe wood. An electronic scanner surveys the log as it is delivered to asupport and obtains log profile data which is transmitted to a computer.Signals sent by the computer to each of the saws cause the saws to takeup positions which ensure that the log is cut into optimum randomlengths. The Murphy et al. system utilizes a reference datum line orcutting plane (see column 1, lines 55-56) for positioning the log.Murphy et al. disclose a “reach out” cylinder 126 and an end plate, butthese are used to assess the position of the butt end of the log and donot push the log into any particular position. The log therefore remainsin its initial rest position. Murphy et al. also disclose a scanner 100which may use conventional single or double axis techniques for scanning(see column 4, lines 28-29) as well as a master control unit 110.

U.S. Pat. No. 4,468,993, granted Sep. 4, 1984, McCown et al., disclosesa log bucking station in which a log is scanned to determine its sizeand shape. The scan data is analyzed by a computer which determines theoptimum locations for cuts on the log. The proposed cut locations areoptically displayed on the log by a laser for inspection by theoperator. The operator can overrule the computer. McCown et al. permitthe distance between the pairs of saws to be varied because the saws runon tracks. By varying the distance between the two travelling saws 26and 28, it is said that it is possible to optimize the saw cutlocations.

SUMMARY OF INVENTION

The present invention overcomes or greatly reduces the disadvantages ofknown systems for processing raw logs into debarked random cut lengthsprior to delivery of the logs to a chipping or log sawing apparatus.

The invention is directed to a log processing and cutting systemcomprising: (a) a log infeed deck; (b) a log feeder; (c) a dual quadrantsingulator located downstream of the log feeder; (d) an infeed conveyor;(e) a log barker located downstream of the barker infeed conveyor; (f) abarker outfeed conveyor located downstream of the log debarker; (g) abucking line scanner which scans the debarked log and by means of anassociated computer, determines the log profile of the debarked log anddetermines optimum cutting locations on the log; (h) a conveyor locateddownstream of the bucking line scanner for conveying the scanned log toa bucking line; (i) a cradle in which the scanned log is held; (j) abucking line positioner which contacts an end of the scanned log andmoves it to an optimum position for cutting by a cut-off saw; (k) abucking line cut-off saw which cuts the log at the optimum locationdetermined by the computer from the log profile information ascertainedby the scanner; (l) a bucking line outfeed conveyor located downstreamof the cut-off saw for conveying away the cut log; and (m) a log sorterwhich directs the cut log to a log sorting station.

The dual quadrant singulator can comprise a lower quadrant singulatorand an upper quadrant singulator, the pair of singulators operating incombination to single out and elevate individual logs.

The debarker can incorporate rotating rings, which can hold debarkingknives and the force exerted on the cutting knives and the speed ofrotation of the rings can be varied according to log profilecharacteristics of an individual log. The bucking line scanner candetermine the log profile by three laser scans, to determine the volumeand shape of the log being scanned at incremental log lengths.

The computer can instruct the cut-off saw to move in advance of the logreaching the cradle in order to minimize saw travel during the logcutting operation. The log positioner can comprise a hydraulic pistonand cylinder, the piston extending a specified distance as determined bythe computer, based on log profile and volume data as determined by thelog scanner, and thereby positioning the log in optimum position.

The system can include a pair of spaced apart cut-off saws, thelocations of the pair of cut-off saws being variable according tooptimum saw location cut points on the log to be cut, as determined bythe computer based on log scan data determined by the scanner.

The invention is also directed to a method of processing and cuttinglogs comprising: (a) singulating logs using a dual quadrant singulator;(b) debarking the logs using a variable speed ring and knife system; (c)scanning the debarked log by means of an associated computer, whichdetermines the log profile of the debarked log and determines optimumcutting locations on the log; (d) conveying the scanned log to a buckingline cradle; (e) using a bucking line positioner which contacts an endof the scanned log and moves it to an optimum position for cutting; (f)cutting the log at the optimum locations as determined by the computerfrom the log profile information ascertained by the scanner andaccording to the positioner; (g) conveying the cut log away from thecutting area; and (h) sorting the cut log according to a command fromthe computer.

The dual quadrant singulator can comprise a lower quadrant singulatorwhich can lift the log to a first elevation and an upper quadrantsingulator, which can lift the log to a second elevation. The rotatingrings of the debarker can hold cutting knives and the force exerted bythe cutting knives on the log and the speed of rotation of the rings canbe varied according to log profile characteristics of an individual log.

The scanning of the log can be done by three laser scans, whichdetermine the volume and shape of the log being scanned at incrementallog lengths. A computer can command a saw to move in advance of the logreaching the cradle to thereby minimize saw travel during the logcutting operation. The log can be positioned in the cradle by a pistonwhich can extend a specified distance as determined by the computer,based on log profile and volume data as determined by the log scanner,and thereby positioning the log in optimum position. The log can be cutat two locations, the locations of the cuts being determined as optimumby the computer based on log scan data ascertained by the scanner.

BRIEF DESCRIPTION OF DRAWINGS

In drawings which illustrate specific embodiments of the invention, butwhich should not be construed as restricting the spirit or scope of theinvention in any way:

FIG. 1 is a schematic plan of the log processing mill showing thegeneral arrangement and sequence of the log processing equipment andprocess.

FIG. 2 is a detail schematic plan of the quadrant/barker area showingthe general arrangement of the log singulating and debarking equipment.

FIG. 3 is an end elevation of the dual log quadrant feeder.

FIG. 4 is a schematic plan of the cut-off-saw bucking area showing thegeneral arrangement of the log handling, sawing and cut log conveyingand sorting equipment.

FIG. 5 is an end elevation of the cut-off saw and log bucking cradle.

FIGS. 6a, 6 b and 6 c are plan, side and end elevations of the cut-offsaw area log positioner.

FIG. 7 is an end section view of the raw log collecting and dualquadrant area, taken along section line 1 of FIG. 1.

FIG. 8 is an end section view of the dual side by side log barkers,taken along section line 2 of FIG. 1.

FIG. 9 is an end section view of the dual and cut log take away deck,taken along section line 3 of FIG. 1.

FIG. 10 is a schematic of the computer monitor display showing scannedlog profile form the scanner.

FIG. 11 is a schematic of the computer monitor display showing variablesof the log bucking system.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE LOG PROCESSING MILL

A log handling and cutting system which cuts logs into lengths, andallows for maximum use of fiber is disclosed. The system includesequipment for singulating the logs, optimally removing the bark from thelogs, scanning the true log image, cutting the logs to length, andsorting the cut logs arranged in a sequence of coupled operations. Thelogs are singulated using a dual quadrant singulation system to providemaximum singulation reliability, thereby allowing a single operator toattend to this process. Once singulated, the logs are fed automaticallyinto a debarker where the diameter and volume are scanned anddebarker-operating parameters are set for optimum bark removal. The logis then scanned, tree length, using a unique scanning system, whichdetermines the true image of the log. This enables the determination bycomputer of the optimum bucking solution of the log as well as a propersorting of the optimum random lengths. The saws are adjusted in responseto the computer solution and the log is positioned by a positioneraccording to a computer generated reference datum. This results in thelog being positioned for cutting to the optimum random lengths. Acommand signal is sent from the computer to the log sorting system,which tracks the position of the random lengths and allows them to besorted to the appropriate sort storage bin.

This subject invention optimizes the debarking of the logs by usinginput variables of log diameter, tool overlap, tool speed (SFPM—surfacefeet per minute), and required tool tip force to determine the debarkerfeedspeed, debarker ring RPM and the applied pressure to the debarkertools (PSI). The applied pressure calculation takes into account theeffects of centripetal acceleration on the tool arms at a given logdiameter to ensure that the correct and optimum pressure is applied todebarking tools.

In the system according to the invention, the logs are first singulatedfrom a log pile using a dual quadrant feed arrangement which enableshigh log handling rates with minimal intervention by an attendant. Oncesingulated, the log is fed automatically in a variable speed ring styledebarker where log diameter information is collected and the debarkingprocedure is optimized for tool overlap, feedspeed, ring RPM, and toolpressure. This combination minimizes cutting overlap and wasted whitewood. This debarking process is adjusted dynamically by a computer asthe log diameter is changed down the log length (since logs are notperfect cylinders). After debarking, the log is scanned over its entiretree length on a belt with a triple combination scanner. This scannersystem calculates the log length, log volume and the true shapecross-section of the log down its length thereby generating a true shapeimage of the log. This data includes sweep, taper, crooks and other logimperfections. This data is then transmitted to an optimizing computer,which rapidly analyzes the data and determines the optimum cutlocations. The debarked and scanned log is then transferred transverselyto a queuing cradle and then into a cut cradle. As soon as the logreaches the cut cradle, a unique log positioner locates the end of thelog in relation to the moveable saw positions and pushes the log intooptimum position for cutting. Once the log is cut, the cut portions aretaken away and the saws are able to move to their next requiredposition, while a new log is being transferred to the cut cradle. Thelog that ha s been cut into sections is unloaded onto a conveyor beltand is transferred to the cut piece sorting area. While this transfer isbeing performed, the new log is being cut. This overlap of infeed,cutting and outfeed cycles reduces log handling time and allows a smoothand efficient process to be performed in the log cut-off saw area of thesystem.

Referring to the drawings, FIG. 1 illustrates a schematic plan of theoverall log processing system and equipment including the generalarrangement and sequence of the log processing equipment from the rawlog collection area to the finished debarked and cut log area. FIG. 1illustrates a parallel log processing line whereby two trains of rawlogs can be debarked and cut simultaneously. It will be understood thatonly one log train can be used or that further parallel log processinglines can be added.

As seen in schematic plan in FIG. 1, the overall dual parallel logsorting, singulating, debarking and log cutting trains are illustratedgenerally by reference numeral 2. The first barker infeed deck 4 and thesecond corresponding barker infeed deck 6 provide locations where theraw log grappler 3 can lift raw logs from a log pile which is suppliedby trucks hauling raw logs from the timber stand, and dumping the logson the decks 4 and 6.

The first quadrant barker feeder 8 and the second quadrant barker feeder10 feed raw logs from the corresponding first and second barker infeeddecks 4 and 6 to corresponding first dual quadrant singulator 12 andsecond dual quadrant singulator 14. The first and second stream of rawlogs singulated by the first and second dual quadrant singulators 18 and14 are dropped onto corresponding first barker infeed conveyor 16 (firstsection) and second barker infeed conveyor 18 (first section). Once theraw logs reach the ends of the first and second conveyors 16 and 18,they are conveyed further by the corresponding first barker infeedconveyor 20 (second section) and second barker infeed conveyor 22(second section). The conveyors 20 and 22 then feed the respectivestreams of raw logs to the first debarker 24 and the second debarker 26.The first and second debarkers 24 and 26 are unique and have automaticvariable ring speed, variable cutting tool pressure, log diameteradjustment capability and variable log speed handling capability. Thisminimizes bark cutting overlap (which is wasteful and time consumingbecause the rotating blades retrace debarked area) and depth of cutwhite wood (which is wasted).

After the first and second raw logs have been optimally debarked, theyare conveyed away from the first and second barkers 24, 26 by firstbarker outfeed conveyor 28 and second barker outfeed conveyor 30. Thebarked first and second logs are then passed respectively through afirst bucking line scanner 32 and a second bucking line scanner 34,where the log profiles of the debarked logs are profiled by a triple logscanning system, which transmits the scan data to a computer. The triplescanners, in a preferred embodiment, are laser scanners and continuouslydetermine the log diameter, the log profile including curves, crooks,taper, and sweep, as well as volume. The computer is then able from thisdata to determine optimum saw cut locations so as to maximize the amountof useful timber that can be cut from each log.

Once the first and second logs have been scanned, and the scan datatransmitted to and analyzed by the computer, they are conveyedrespectively by first bucking line conveyor 36 and second bucking lineconveyor 38. At that point, the first and second barked and scanned logsare swept to the first bucking line and the second bucking linerespectively by first sweep 40 and second sweep 42. The first and secondlogs then are handled by first bucking line stop-loader and secondbucking line stop-loader 44 and 46 respectively. The logs are thendropped onto first bucking line cradle 48 and second bucking line cradle50 respectively.

The first scanned and barked log lying in the first bucking line cradle48 and the second scanned and barked log lying in the second buckingline cradle 50 are then, as determined by the computer scan, accordingto optimum saw cut points, positioned by first bucking line positioner52 and second bucking line positioner 54. In other words, the butt endsof the respective pair of logs are contacted respectively by the firstpositioner 52 and second positioner 54 and moved by the positioners tothe optimum locations on the first and second cradles 48 and 50 forcutting by the two pairs of saw. This feature of the two log buckingareas is unique and is highly efficient. Once the first and second logsare optimally positioned respectively by the first bucking linepositioner 52 and the second bucking line positioner 54, they arerespectively cut by the first pair of bucking line saws 56 and thesecond pair of bucking line saws 58. FIG. 1 shows a pair of cut-off saws56 and 58 in both the first and second log handling lines, but only onesaw in each line can be used, or additional saws can be added. One sawmay be all that is required for short logs. Long logs may require threeor more logs.

Once the first and second logs have been cut into respective segments bythe first and second bucking saws 56 and 58, the logs are conveyed awayfrom the bucking saws 56 and 58 by respective first bucking line outfeedconveyor 60 and second bucking line outfeed conveyor 62. The velocity oftravel of the first and second logs is accelerated respectively by firstbucking line log accelerator 64 and second bucking line log accelerator66. The propelled logs then reach respectively the first bucking linelog sort conveyor 68 and the second bucking line log sort conveyor 70.Subsequently, the first and second logs are swept laterally by firstbucking line sweep No. 1 and log catcher 72, and second bucking linesweep No. 1 and log catcher 74.

As shown in FIG. 1, the log bucking area is set up with a pair ofcut-off saws in each of the parallel log bucking lines, which therebycuts the scanned logs into three separate components. A command signalis sent from the computer to the log sorting system, which tracks theposition of the random log lengths and enables them to be sorted to theappropriate sort storage bin.

The log components, according to the length of each cut segment, aresorted by first bucking line sweep No. 76 and second bucking line sweepNo. 78 and first bucking line sweep No. 3 and second bucking line sweepNo. 80, 82, as determined by the computer and according to the length ofthe segments that have been cut for each cut log.

FIG. 1 also shows the location of the barking area operator cab 84 andthe bucking area operator cab 86. An operator sitting in the first cab84 can conveniently view the log deck and singulating area and intervenewhen something goes amiss in the raw log handling area, such as two logsbeing dropped on a conveyor belt, or a log ends up crossways. Anoperator sitting in the cab 86 can conveniently view the bucking areaand intervene if a hitch of some sort develops in the bucking area. Thecomputer is housed in computer room 88. The log sorting barking andbucking system according to the invention can be operated quickly andefficiently by only two operators, whereas previously nine or morepersonnel were required to handle the same volume of logs forprocessing, barking and cutting.

FIG. 2 illustrates a detailed enlarged schematic plan of thequadrant/barker area including the general arrangement of the raw logprocessing equipment. The raw log grappler 3 loads raw logs from a trucksupplied log pile onto the first barker infeed deck 4 and the secondbarker infeed deck 6 respectively. From there, the respective first andsecond logs are moved to first quadrant barker feeder 8 and secondquadrant barker feeder 10, as indicated by the arrows. The first andsecond logs are then singulated by the first dual quadrant singulator 12and the second dual quadrant singulator 14 respectively.

The first and second singulated logs are then conveyed to the respectivebarkers 24 and 26 by the first barker infeed conveyor 16 and the secondbarker infeed conveyor 18 respectively. Reference numerals 16 and 18denote the first sections of the respective log conveyors 16 and 18. Thefirst and second singulated logs are then conveyed from the firstsection of the first and second infeed conveyors 16 and 18 to the secondsections of first barker infeed conveyor 20 and the second section ofbarker infeed conveyor 22. First and second section conveyors areadvantageous because they circumvent the need to have long breakdownprone conveyors.

The first and second logs are then fed respectively to the firstdebarker 24 and the second debarker 26. The first debarker 24 and thesecond debarker 26 are of unique construction because they utilizevariable ring speed, rather than constant ring speed, variable barkremoving knife pressures, and variable log diameter handling capabilityin order to achieve maximum debarking efficiency and minimum white woodcuttings. The foregoing variables also minimize bark cutting overlap,thereby resulting in improved efficiency.

FIG. 3 illustrates an end elevation of a dual log quadrant feeder 12(also known as a singulator). As can be seen in FIG. 3, the dualquadrant singulator 12 is constructed of a lower large diameter quadrantfeeder 13 and a smaller diameter upper quadrant feeder 15. Lowerquadrant feeder 13 has a counterbalance weight 17, while upper quadrantfeeder 15 has a similar balance weight. These weights reduce the forcerequired to lift the respective quadrant. The combination of lower andupper quadrant feeders has been found to be very advantageous inensuring proper singulation of the raw logs which can have manyimperfections such as broken branch stumps, crooks, twists, sweeps, andthe like, thus increasing the difficulty of singulating the logs on areliable and trouble-free basis. The dual feeders 13 and 15 increase thelikelihood that the logs are properly singulated before they are dumpedonto the barker infeed conveyor 16. This results in minimized down timedue to the dual quadrants inadvertently picking up two or more logs, orno logs at all.

FIG. 4 illustrates an enlarged detailed schematic plan of the cut-offsaw area showing the general arrangement of the log sawing and handlingequipment. After the first and second lines of raw logs have beendebarked, they are conveyed away from the first and second barkers byfirst barker outfeed conveyor 28 and second barker outfeed conveyor 30.The barked first and second logs are then passed respectively through afirst bucking line scanner 32 and a second bucking line scanner 34,where the log profiles of the debarked logs are profiled by a triple logscanning system, and accessed by the computer.

Once the first and second logs have been scanned, they are conveyedrespectively by first bucking line conveyor 36 and second bucking lineconveyor 38. The first and second barked and scanned logs are then sweptto the first bucking line and the second bucking line respectively byfirst sweep 40 and second sweep 42. At that point, the first and secondlogs are handled by first bucking line stop-loader and second buckingline stop-loader 44 and 46 respectively. The logs are then dropped ontofirst bucking line cradle 48 and second bucking line cradle 50respectively.

The first scanned and barked log lying in the first bucking line cradle48 and the second scanned and barked log lying in the second buckingline cradle 50 are then, as determined by the computer scan, arerespectively positioned by the first bucking line positioner 50 and thesecond bucking line positioner 54 to move them to optimum saw cutpositions. This feature of the log bucking areas is unique and highlyefficient. Once the first and second logs are located respectively bythe first bucking line positioner 52 and the second bucking linepositioner 54, in the optimum positions, they are respectively cut bythe first bucking line saw 56 and the second bucking line saw 58. Asshown in FIG. 4, there are a pair of cut-off saws 56 and 58 in both thefirst and second log handling lines. The pairs of cut-off saws 56 and 58are mounted on rollers and tracks so the distances between the pairs ofsaws in the respective cut saws 56 and 58 can be varied. The positionsare controlled by the computer.

Once the first and second logs have been cut into respective segments bythe first and second bucking saws 56 and 58, the logs are conveyed awayfrom the bucking saws 56 and 58 by respective first bucking line outfeedconveyor 60 and second bucking line outfeed conveyor 62. The velocity oftravel of the first and second logs is accelerated respectively by firstbucking line log accelerator 64 and second bucking line log accelerator66. The logs then reach respectively the first bucking line log sortconveyor 68 and the second bucking line log sort conveyor 70.Subsequently, the first and second logs are swept laterally by firstbucking line sweep No. 1 and log catcher 72, and second bucking linesweep No. 1 and log catcher 74. As shown in FIG. 4, the log bucking areais set up with a pair of cut-off saws in each of the parallel logbucking lines, which thereby cuts the scanned logs into three separatesegments. The components, according to the length of each cut segment,are sorted by first bucking line sweep No. 76 and second bucking linesweep No. 78 and first bucking line sweep No. 3 and second bucking linesweep No. 80, 82, as determined by the computer and according to thelength of the segments that have been cut for each cut log, into threeseparate groups as indicated by the arrows.

FIG. 5 illustrates an end elevation of one of the cut-off saws with logcradle and outfeed conveyor. The cut-off saw 50 is shown in both anupper and lower position (the latter shown in dotted lines). The buckingsaw 56 (cut-off saw) has a counterweight 57 to reduce energy consumptionwhen the saw is raised and lowered.

As seen in end view in FIG. 5, the log (leftmost circle) enters thecut-off saw area on first bucking line conveyor 36. A sweep (not shown)then moves the log laterally to a notch in the first bucking linestop-loader 44. When stop-loader 44 is rotated to move the notch to theright (see dotted line) the log drops downwardly into first bucking linecradle 48. At that point, and to minimize travel time, the saw 56 hasalready been lowered in advance to an elevation slightly higher than thelog diameter. This is determined by the computer from the log scan takenpreviously. When the log is held in the cradle 48, the saw 56 then cutsit at the optimum location as determined by the log scan. Once the logis cut, then the second stop 49 rotates to the right and permits the cutlog to drop from the notch onto bucking line outfeed conveyor 60.

FIGS. 6a, 6 b and 6 c illustrate respectively plan, side and endelevations of the cut-off saw area log positioner. The position ofpiston 53, according to scan data received from the scanner, andanalyzed by the computer, maximizes the location of the cut points onthe debarked log lying in the cradle 48. The log positioner 52 extendsthe hydraulic piston 53 against the butt end of the log and moves it toan optimum log cutting location in the cradle 48 (see FIG. 5), asdetermined by the computer. FIG. 6(b) illustrates a side view of the logpositioner 52 with the piston 53 retracted. FIG. 6(c) illustrates an endelevation of the log positioner 52.

The positioner 52 is innovative and unique. It enables the log lying inthe cradle 48, in stop 49, to be moved to any optimum location asdetermined by the computer. It also enables the log to be positioned sothat only the small end of the log is cut off and goes to hog. This istrue whether the log is lying in the cradle head first or tail first. Inthis way, the more valuable butt log ends with greater diameter are notwasted. The log positioner 52, by being controlled by the computer, alsoenables the log to be positioned regardless of any central datum line.It is therefore not necessary to calculate log position according to adatum line. The computer, in combination with the log positioner 52,also controls the positions of the first and second cut-off saws 56 and58, so that in combination, optimum lengths of log are cut, therebyminimizing wood loss due to log sweep, log crooks, and other deformitiesin the log.

FIG. 7 is an end section view of the raw log collecting and dualquadrant area, taken along section line 1 of FIG. 1. As seen in FIG. 7,the pair of dual quadrant log singulators 12 and 14 are shown on eachside of the log decks 4 and 6. The log grappler 3, as shown, drops rawlogs on the respective first barker infeed deck 4 and the second barkerinfeed deck 6. After the logs have been singulated by the first dualquadrant singulator 12 and second dual quadrant singulator 14respectively, they are moved to first barker infeed conveyor 16 andsecond barker infeed conveyor 18 respectively.

FIG. 8 is an end section view of the dual side by side log debarkers,taken along section line 2 of FIG. 1. As seen in FIG. 8, the parallelpositioned first debarker 24 and second debarker 26 are shown in side byside relation directly downstream from the conveyors 16 and 18 (see FIG.7). The barking area operator cab 84, while not shown, is locatedimmediately upstream of the pair of barkers 24 and 26 and enables theoperator to view the entire log deck and singulating area.

FIG. 9 is an end section view of the dual and cut log take away deck,taken along section line 3 of FIG. 1. As seen in FIG. 9, the firstbarker outfeed conveyor 28 and second barker outfeed conveyor 30 areshown in side by side relation. A pair of log sort conveyors 68 and 70are also shown. While not shown in FIG. 9, the first, second and thirdgroup of bucking line sweeps 72, 76 and 80, and the second trio ofsecond bucking line sweeps 74, 78 and 82 (see FIG. 1) move the cut logslaterally onto the sort deck and ultimately to a step feeder 90, whichconveys the logs away to a sawmill, or some other suitable cut loghandling facility.

FIG. 10 is a schematic of the computer monitor display showing scannedlog profile form the scanner. As seen in FIG. 10, the scanned profilesof two parallel logs are shown in the upper portion of the screen. Thelocations of the two cuts on each log are also shown. The profiles ofthree log sections are shown in the lower portion of the screen.

FIG. 11 is a schematic of the computer monitor display showing variablesof the log bucking system. FIG. 11 displays, among other things, thethree sort decks, log pusher position (actual and demand) for each sawand total logs cut in line 1 and line 2 as of the time of the display.

As will be apparent to those skilled in the art in the light of theforegoing disclosure, many alterations and modifications are possible inthe practice of this invention without departing from the spirit orscope thereof. Accordingly, the scope of the invention is to beconstrued in accordance with the substance defined by the followingclaims.

What is claimed is:
 1. A log processing and cutting system comprising:(a) a log infeed deck; (b) a log feeder; (c) a dual quadrant singulatorlocated downstream of the log feeder; (d) an infeed conveyor; (e) a logbarker located downstream of the barker infeed conveyor; (f) a barkeroutfeed conveyor located downstream of the log debarker; (g) a buckingline scanner which scans the debarked log and by means of an associatedcomputer, determines the log profile of the debarked log and determinesoptimum cutting locations on the log; (h) a conveyor located downstreamof the bucking line scanner for conveying the scanned log to a buckingline; (i) a cradle in which the scanned log is held; (j) a bucking linepositioner which contacts an end of the scanned log and moves it to anoptimum position for cutting by a cut-off saw; (k) a bucking linecut-off saw which cuts the log at the optimum location determined by thecomputer from the log profile information ascertained by the scanner;(l) a bucking line outfeed conveyor located downstream of the cut-offsaw for conveying away the cut log; and (m) a log sorter which directsthe cut log to a log sorting station.
 2. A system as claimed in claim 1wherein the dual quadrant singulator comprises a lower quadrantsingulator and an upper quadrant singulator, the pair of singulatorsoperating in combination to single out and elevate individual logs.
 3. Asystem as claimed in claim 1 wherein the debarker incorporates rotatingrings, which hold debarking knives and the force exerted on the cuttingknives and the speed of rotation of the rings are varied according tolog profile characteristics of an individual log.
 4. A system as claimedin claim 1 wherein the bucking line scanner determines the log profileby three laser scans, to determine the volume and shape of the log beingscanned at incremental log lengths.
 5. A system as claimed in claim 1wherein the computer instructs the cut-off saw to move in advance of thelog reaching the cradle in order to minimize saw travel during the logcutting operation.
 6. A system as claimed in claim 1 wherein the logpositioner comprises a hydraulic piston and cylinder, the pistonextending a specified distance as determined by the computer, based onlog profile and volume data as determined by the log scanner, andthereby positioning the log in optimum position.
 7. A system as claimedin claim 1 wherein the system includes a pair of spaced apart cut-offsaws, the locations of the pair of cut-off saws being variable accordingto optimum saw location cut points on the log to be cut, as determinedby the computer based on log scan data determined by the scanner.
 8. Amethod of processing and cutting logs comprising: (a) singulating logsusing a dual quadrant singulator; (b) debarking the logs using avariable speed ring and knife system; (c) scanning the debarked log bymeans of an associated computer, which determines the log profile of thedebarked log and determines optimum cutting locations on the log; (d)conveying the scanned log to a bucking line cradle; (e) using a buckingline positioner which contacts an end of the scanned log and moves it toan optimum position for cutting; (f) cutting the log at the optimumlocations as determined by the computer from the log profile informationascertained by the scanner and according to the positioner; (g)conveying the cut log away from the cutting area; and (h) sorting thecut log according to a command from the computer.
 9. A method as claimedin claim 8 wherein the dual quadrant singulator comprises a lowerquadrant singulator which lifts the log to a first elevation and anupper quadrant singulator, which lifts the log to a second elevation.10. A method as claimed in claim 8 wherein the rotating rings of thedebarker hold cutting knives and the force exerted by the cutting kniveson the log and the speed of rotation of the rings are varied accordingto log profile characteristics of an individual log.
 11. A method asclaimed in claim 8 wherein the scanning of the log is done by threelaser scans, which determine the volume and shape of the log beingscanned at incremental log lengths.
 12. A method as claimed in claim 8wherein a computer commands a saw to move in advance of the log reachingthe cradle to thereby minimize saw travel during the log cuttingoperation.
 13. A method as claimed in claim 8 wherein the log ispositioned in the cradle by a piston which extends a specified distanceas determined by the computer, based on log profile and volume data asdetermined by the log scanner, and thereby positioning the log inoptimum position.
 14. A method as claimed in claim 8 wherein the log iscut at two locations, the locations of the cuts being determined asoptimum by the computer based on log scan data ascertained by thescanner.